Conventionally, in a lens, such as an eyeglass lens, which is put into a predetermined frame, a processing step is provided of cutting, by cutting processing, the surrounding (end surface) of a lens which serves as a precursor to process the lens into a shape corresponding to the frame.
Although in the processing, in general, with a chuck device, the lens is held so as to be chucked from the front and rear surfaces of the lens, since the cutting edge of a processing device makes contact with the lens from the end surface side so as to press the lens, an adhesive tape is adhered to a contact portion between a chuck tip end and the surface of the lens so that even when a lens whose dynamic frictional coefficient is low is chucked, the shaft position of the chuck device is prevented from being displaced by the pressing force thereof (that is, the holding position of the lens is prevented from being displaced). As an example of a means for preventing the holding position of the lens from being displaced with such an adhesive tape, Patent Document 1 is shown.